drivers/w1/slaves/w1_bq27000.c

   1 /*
   2  * drivers/w1/slaves/w1_bq27000.c
   3  *
   4  * Copyright (C) 2007 Texas Instruments, Inc.
   5  *
   6  * This file is licensed under the terms of the GNU General Public License
   7  * version 2. This program is licensed "as is" without any warranty of any
   8  * kind, whether express or implied.
   9  *
  10  */
  11
  12 #include <linux/kernel.h>
  13 #include <linux/module.h>
  14 #include <linux/device.h>
  15 #include <linux/types.h>
  16 #include <linux/platform_device.h>
  17 #include <linux/mutex.h>
  18 #include <linux/power/bq27x00_battery.h>
  19
  20 #include "../w1.h"
  21 #include "../w1_int.h"
  22 #include "../w1_family.h"
  23
  24 #define HDQ_CMD_READ    (0)
  25 #define HDQ_CMD_WRITE   (1<<7)
  26
  27 static int F_ID;
  28
  29 static int w1_bq27000_read(struct device *dev, unsigned int reg)
  30 {
  31         u8 val;
  32         struct w1_slave *sl = container_of(dev->parent, struct w1_slave, dev);
  33
  34         mutex_lock(&sl->master->bus_mutex);
  35         w1_write_8(sl->master, HDQ_CMD_READ | reg);
  36         val = w1_read_8(sl->master);
  37         mutex_unlock(&sl->master->bus_mutex);
  38
  39         return val;
  40 }
  41
  42 static struct bq27000_platform_data bq27000_battery_info = {
  43         .read   = w1_bq27000_read,
  44         .name   = "bq27000-battery",
  45 };
  46
  47 static int w1_bq27000_add_slave(struct w1_slave *sl)
  48 {
  49         int ret;
  50         struct platform_device *pdev;
  51
  52         pdev = platform_device_alloc("bq27000-battery", -1);
  53         if (!pdev) {
  54                 ret = -ENOMEM;
  55                 return ret;
  56         }
  57         ret = platform_device_add_data(pdev,
  58                                        &bq27000_battery_info,
  59                                        sizeof(bq27000_battery_info));
  60         if (ret)
  61                 goto pdev_add_failed;
  62         pdev->dev.parent = &sl->dev;
  63
  64         ret = platform_device_add(pdev);
  65         if (ret)
  66                 goto pdev_add_failed;
  67
  68         dev_set_drvdata(&sl->dev, pdev);
  69
  70         goto success;
  71
  72 pdev_add_failed:
  73         platform_device_put(pdev);
  74 success:
  75         return ret;
  76 }
  77
  78 static void w1_bq27000_remove_slave(struct w1_slave *sl)
  79 {
  80         struct platform_device *pdev = dev_get_drvdata(&sl->dev);
  81
  82         platform_device_unregister(pdev);
  83 }
  84
  85 static struct w1_family_ops w1_bq27000_fops = {
  86         .add_slave      = w1_bq27000_add_slave,
  87         .remove_slave   = w1_bq27000_remove_slave,
  88 };
  89
  90 static struct w1_family w1_bq27000_family = {
  91         .fid = 1,
  92         .fops = &w1_bq27000_fops,
  93 };
  94
  95 static int __init w1_bq27000_init(void)
  96 {
  97         if (F_ID)
  98                 w1_bq27000_family.fid = F_ID;
  99
 100         return w1_register_family(&w1_bq27000_family);
 101 }
 102
 103 static void __exit w1_bq27000_exit(void)
 104 {
 105         w1_unregister_family(&w1_bq27000_family);
 106 }
 107
 108
 109 module_init(w1_bq27000_init);
 110 module_exit(w1_bq27000_exit);
 111
 112 module_param(F_ID, int, S_IRUSR);
 113 MODULE_PARM_DESC(F_ID, "1-wire slave FID for BQ device");
 114
 115 MODULE_LICENSE("GPL");
 116 MODULE_AUTHOR("Texas Instruments Ltd");
 117 MODULE_DESCRIPTION("HDQ/1-wire slave driver bq27000 battery monitor chip");